This invention pertains generally to pumps for dispensing gasoline and other liquid petroleum products and more particularly to an encoder for providing an output signal corresponding to the price of the product dispensed.
Pumps of the type commonly used for dispensing gasoline and other liquid petroleum products generally include a flow responsive mechanical computer for determining the total sales price or cost of the product dispensed. Such computers generally include price display wheels and a Geneva movement for advancing the wheels in accordance with the flow of product through the pump and the unit price of the product. Examples of such computers are the Model 56 and Model 101 gas pump computers manufactured by Veeder Root.
In the past, there have been attempts to attach devices to the price volume computers of gasoline pumps to provide digital electrical signals corresponding to the price of the gasoline dispensed. The signals are transmitted to suitable equipment for totalization, recordation or other desired processing. The devices heretofore provided for this purpose have been subject to a number of problems and disadvantages, including inaccuracy and requiring frequent maintenance. Moreover, the devices have had to be specially adapted for different types of computers, and since the devices remain connected to the computers at all times, they can generate spurious pulses when the pumps are reset.